I want to remove them but not if I might use them later.
(If I am keeping them they need stainless screws at the very least).

Thanks...

Hmmm- I am thinking that somewhere in my dim past, I saw a umbrella/awning that mounted that way. After it was slid into the holes, some sort of doo-dad would align with the small hole to limit the rotation of the shaft. Larry

Nothing like that on my UHaul, although I have a 16' one. What we do have in the location of the upper one is a porch light.

Something that works for us if you are interested. We use a FirstUp from Walmart instead of an awning. If you prop its legs up against (or right next to - if it brushes the Uhaul, we put a towel between the leg and the trailer) the trailer and extend it to its full height, it makes a nice additional room. It is amazing how nice that additional space is. We spend most of our time out there. It keeps a lot of the bugs out too.